Terminal for pneumatic tube dispatch system

ABSTRACT

A terminal for a pneumatic tube system in which the system transmit and receive tubes have spaced ends terminating at the terminal in generally vertically disposed orientation, including a terminal tube section extending upwardly from the receive tube, an elastically compressible braking element mounted at the upper end of the terminal tube section for arresting the forward motion of the received carrier and thereafter forceably directing the carrier rearwardly in a reverse direction, a detent spaced from the compressible braking element to engage the forward end of a received carrier at the periphery thereof to cause it to pivot thereabout as it is reversely directed by compressed brake element, a carrier opening in the side of the terminal tube section through which a pivoting carrier reversely directed by the compressed brake element is adapted to exit, and a carrier guide means extending outwardly and downwardly from the lower extremity of the tube section side opening to the transmit tube for slideably engaging the rear end of a pivoting carrier as it passes through the opening to guide the carrier to a position outside the tube section.

United StatesPatent Rudder et a1.

[ TERMINAL FOR PNEUMATIC TUBE DISPATCH SYSTEM [75] Inventors: Joel Rudder, Rockaway; Adam Weissmuller, Pompton Plains, both of NJ.

[7 3] Assignee: The Mosler Safe Company,

Hamilton, Ohio 22 Filed: Oct. 17,1973

21 Appl. No.: 407,274

[52] U.S. C1 243/19, 243/24, 243/38 [51] Int. Cl. B65g 51/32 [58] Field of Search 243/1, 19, 20, 2'3, 24, 243/25, 28, 38; 302/1, 2

[56] References Cited UNITED STATES PATENTS 1,383,194 6/1921 Engebretsen 243/24 3,756,536 9/1973 Weissmuller et a1. 243/19 Primary Examiner-Richard A. Schacher Assistant Examiner-James L. Rowland Attorney, Agent, or Firm-Wood, Herron & Evans 3,830,446 Aug. 20, 1974 [57 ABSTRACT A terminal for a pneumatic tube system in which the system transmit and receive tubes have spaced ends terminating at the terminal in generally vertically disposed orientation, including a terminal tube section extending upwardly from the receive tube, an elastically compressible braking element mounted at the upper end of the terminal tube section for arresting the forward motion of the received carrier and thereafter forceably directing the carrier rearwardly in a reverse direction, a detent spaced from the compressible braking element to engagethe forward end of a received carrier at the periphery thereof to cause it to pivot thereabout as it is reversely directed by compressed brake element, a carrier opening in the side of the terminal tube section through which a pivoting carrier reversely directed by the compressed brake el- I ement is adapted to exit, and a carrier guide means extending outwardly and downwardly from the lower extremity of the tube section side opening to the transmit tube for slideably engaging the rear end of a pivot- 7 Claims, 16 Drawing Figures PATENIEH AUG 2 0 i974 SHED 10f 2 TERMINAL FOR PNEUMATIC TUBE DISPATCH SYSTEM This invention relates to pneumatic tube dispatch systems and more particularly to a terminal for use with such systems which facilitate carrier receipt and transmission.

Pneumatic tube systems propel carriers between distant stations through a tube by means of a pressure differential which exists across the carrier in the direction of carrier transport. Such systems are provided with terminals at the system stations to facilitate transmission and/or receipt of carriers. Such terminals, if they are to receive carriers, advantageously include some form of braking means for gradually arresting the forward motion of a carrier transmitted to the terminal from a distant station. This avoids carrier damage and excessive noise and vibration which would otherwise occur were such braking means eliminated and the forward motion of a rapidly moving carrier to be abruptly stopped at the terminal. It is also desirable to provide at terminals adapted to receive carriers some means for positioning the carrier such that it can be conveniently manually removed by the operator once it has come to rest. Finally, and for purposes of economy, pneumatic terminals, particularly where such are designed to both receive and transmit a carrier, advantageously are compact and utilize a minimum number of moving parts.

Accordingly, it has been an object of this invention to provide a terminal capable of receiving carriers which minimizes damaging impact upon receipt of a carrier and presents it in a disposition facilitating convient manual withdrawal once it has come to rest, and yet is compact and utilizes a minimum number of moving elements. This objective has been accomplished in accordance with a preferred embodiment of the invention by providing, in combination, a tube extension for a system receive tube in which the extension has a lower end communicating with the upper end of the system receive tube through which received carriers pass upwardly following exit from the system receive tube, an elastically deformable brake means mounted at the upper end of the receive tube extension for arresting the forward motion of the carrier and thereafter forceably rearwardly directing the carrier in a reverse direction, a pivot member mounted proximate the upper end of the receive tube extension to engage the forward end of a received carrier at the periphery thereof and cause such to pivot thereabout as it is reversely directed by he brake means, and a carrier exit opening in the side of the receive tube extension through which a pivoting carrier reversely directed by the brake means is adapted to exit for presentment to the operator. In accordance with the foregoing arrangment, the kinetic energy of motion of the carrier is converted into potential energy of the elastically deformable braking ele ment to arrest the forward motion of the carrier without damaging impact, and the arrested carrier forcibly redirected in a reverse direction such that it pivots around the pivot element in the course of which it passes through the exit opening provided in the side of the receive tube extension for presentment to he operator.

In a preferred form of the invention, the foregoing terminal is provided with a carrier guide extending outwardly and downwardly from the side exit opening of the receive tube extension for slideably engaging the rear end of the pivoting carrier as it passes through the exit opening, and an abutment associated with the guide for arresting the sliding motion of the carrier,

such that the carrier remains on the guide supported outside of the tube extension for convenient removal by the operator.

In accordance with a further aspect of the invention, the carrier insertion opening of a system transmit tube is located between the carrier guide and the abutment such that the insertion opening is blocked by a received carrier supported on the guide to prevent insertion therein of a carrier, whereby a terminal adapted to both receive and transmit carrier is provided which is compact and which prevents transmission of a carrier when a received carrier supported on the guide means has not been removed.

Theseand other advantages and objectives of this invention will become more readily apparent from the following description thereof taken in connection with the drawings in which:

FIGS. 1, 2, 3 and 4 are cross sectional views partially in elevation of a preferred embodiment of the combined transmit and received terminal of this invention, showing a carrier in different positions it sequentially occupies during a receive cycle when the carrier has its forward motion arrested by the brake, pivots, and eventually comes to rest supported on the carrier guide;

FIG. 5 is a side elevational view of the preferred embodiment of FIGS. 1-4 showing a carrier in the process of insertion for transmission;

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 1;

FIG. 7 is a cross-sectional view taken along line 77 of FIG. 1;

FIG. 7A is an enlarged cross-sectional view illustrating details of the detent and leaf spring mounting assembly;

FIGS. 8, 9, l0 and 11 are side elevational views of different modifications of the preferred embodiment depicted in FIGS. 1-7, in which the terminal tube section extending from the system receive tube is inclined at different angles to be horizontal;

FIGS. 12, 13, 14 and 15 are schematic elevational views of a received carrier engaged by the pivot memher and the bumper for terminal tube sections disposed at varying angles to the horizontal, showing the forces applied to the carrier by the pivot member, bumper, and the weight of the carrier and its contents.

With reference to FIGS. 1, 6 and 7, one preferred form of this invention is seen to include a system receive tube 10, having an upper, or exit, end 12 through which a carrier C passes or exits, un upwardly direction when propelled by a net pressure force acting in an upwardly direction 15 against the rear end or bottom 14 of the carrier. The system received tube 10, at least at the point where it enters the bottom 16 of a terminal housing 18, is inclined in a generally vertical direction. Also included is a system transmit tube 20 which has its upper, or insertion, end 22 open to facilitate insertion of a carrier for transmission to a distant station when a net pressure force is applied to the inserted carrier in the direction of arrow 24. The transmit tube 20, which also passes through bottom 16 of the terminal housing 18, would typically be connected to the input or suction end of a conventional air blower, while the receive tube 10 would be connected to the output or pressure side of the conventional air blower.

The housing 18 can be fabricated of sheet metal or other appropriate material, and having any configuration suitable for enclosing the various structural elements of the terminal 8. In a preferred form, the housing 18 includes, in addition to the horizontally disposed bottom 16, a horizontally disposed top panel 26, an inclined rear panel 28, a vertical upper front panel 30, an inclined lower front panel 32, and spaced vertical side panels 34, 34, only one of which is shown in FIG. 1. The configuration of the side panels 34, 34, only one of which is shown in FIG. 1. The configuration of the side panels 34, 34 is established by the bottom, top, rear, and upper and lower front panels 16, 26, 28, 30 and 32, to which the side panels 34, 34 are joined, except that a section established by edges 38 and 40 (FIGS. 1 and 6) has been removed to facilitate access to the interior of the housing 18.

Located within the terminal housing 18 is a terminal tube section 42 having a first or lower end 44 communicating with the upper or exit end 12 of the receive tube and a second or upper end 46. A received carrier C is propelled into the terminal tube section 42 via the lower open end 44 which communicates with the upper end 12 of the receive tube 10. Located at the upper end 46 of the terminal tube section 42 is a brake means 48 which in the preferred embodiment takes the form of an elastically deformable solid cyclindrical compressible bumper mounted inside the upper end region 46 of the terminal tube section. The bumper 48, for example, may be fabricated of a closed-cell neoprene foam rubber, having a durometer less than 5 and an axial dimension of approximately 3 inches, in pneumatic tube systems employing carriers 4%" in. diameter with an empty weight of i8 ounces and a velocity of 25 feet per second.

The bumper 48 functions to arrest the forward motion of a received carrier C moving in the direction of arrow by undergoing elastic deformation, or compression, when the forward end 50 of the carrier C abuts the bumper. The extent of compression depends on the momentum of the carrier, i.e., mass of carrier and contents and carrier velocity, and the efiective spring constant of the bumper. When the forward motion of the carrier has been completely arrested and the carrier has come to a complete stop the bumper 48, which is now compressed having converted the kinetic energy of the carrier into potential energy of the compressed bumper, applies a rearward force on the carrier in the direction of arrow 52, as shown in FIG. 2. This rearward force on the carrier in the direction of arrow 52 applied to the carrier by the bumper 48 tends to propel the carrier in a reverse direction in the terminal tube section 42. The carrier-arrest function of the bumper 48, by virtue of the elastic deformation thereof upon carrier abutment, is accomplished without undesirable carrier damage, noise and vibration.

The terminal 8 also includes a pivot member or detent 56. The detent 56 is mounted to the upper end 46 of the terminal tube section 42 by a leaf spring 58 such that the detent 56 normally projects into the terminal tube section sufficiently to mechanically interfere with a received carrier, as best shown in FIG. 7A. Because of the leaf spring mounting of detent 56, the normally inwardly projecting detent does move radially outwardly when the enlarged head 57 at the forward end 50 of the carrier C abuts the inclined surface 51 of the detent as the forward end of the carrier passes the detent in the course of moving toward the bumper 48. The detent 56 is, spaced from the carrier-engaging lower surface 59 of the bumper 48 a distance sufficient to permit the detent to return under spring action to a position projecting into the terminal tube section 42 behind, or below, the enlarged head 57 when the bumper is compressed, as shown in FIG. 2. With the detent 56 in the position shown in FIG. 2, an arrested carrier will pivot counterclockwise about the detent under the action of the combined weight of the carrier and contents and/or the compressed bumper 48, as will be described more fully hereafter.

A carrier opening 64 is provided in the side of the terminal tube section 42 to facilitate exit from the terminal tube section of a received carrier as it pivots about the detent 56. The opening 64 extends in a longitudinal direction from a point proximate the detent 56 downwardly at least a distance equal to the radius R of an are 66 through which the lower end 14 of a received carrier moves in the course of pivoting about the detent 56. With the length of the opening 64 so dimensioned in the longitudinal direction, the lower end 14 of a carrier C pivoting about detent 56 will pass clear of the lower edge of the opening in the course of exiting the terminal tube section 42, as shown in FIG. 3. The width of the opening 64 must exceed the diameter of the enlarged heads 57 and '70 of the carrier to permit free passage of the carrier through the opening 64.

Carrier guide means 72 in the form of a planar inclined panel extends outwardly and downwardly from the lower edge of the opening 64. The guide panel 72 is mounted in the desired position in any suitable manner such as by securing it to the housing 18. The guide panel 72 underlies and slideably engages the rear end 14 of a pivoting carrier as it passes through the side opening 64 of the terminal tube section 42 to guide the carrier to a position substantially outside the terminal tube section with the rear end 14 of the carrier remote from the opening. Additionally, the guide panel 72 operates to support for convenient removal a received carrier after it has pivoted through the opening 64 and come to rest with its head 57 engaged by the upper edge 74 of the guide panel. Preferably, and as shown in FIGS. 1 and 7, the guide panel extends substantially the entire distance between adjacent wall portions of the terminal tube section 42 and the transmission tube 20 to provide maximum support for a carrier which has come to rest thereon.

An abutment 76 inclined upwardly and outwardly at a point proximate the outer edge of the insertion end 22 of the transmit tube 20 is provided. The abutment 76 functions to assist in arresting the sliding motion of the received carrier on the guide panel 72 as well as to hold the carrier in place on the guide panel until it is manually removed by an operator. The panel 72 desirably should be disposed to have a substantial horizontal component to facilitate convenient removal therefrom by the operator. Preferably, both the guide panel 72 and the abutment 76 are provided with a resilient surface layer to minimize noise, vibrations, and damage to the carrier upon engagement therewith in the course of coming to rest on the panel 72 and against the abutment 76.

In view of the placement of the guide panel 72 and abutment 76 on opposite side of the insertion end 22 of the transmit tube 20, a received carrier awaiting manual removal (FIG. 4) overlies the insertion end of the transmit tube. This enhances the compactness of the terminal 8 as well as prevent transmission of a carrier via the tube without first removing the received carrier from the guide panel 72.

In operation, and with reference to FIGS. 1-4, a carrier transmitted from a remote point to the terminal 8 travels in the direction of arrow 15 through the receive tube 10, as a consequence of a net pressure force acting upwardly on the lower end 14 of the carrier C. The moving carrier C enters the terminal tube section 42 via the lower end 44 which communicates with the receive tube 10. The moving carrier continues travelling upwardly in the terminal tube section 42 until its forward end abuts the lower surface 59 of the bumper 48 whereupon the bumper elastically deforms, or compresses, until all forward carrier motion in an upwardly direction has been arrested. At this point wherein the carrier has terminated its forward motion, the kinetic energy of the previously moving carrier has been converted into potential energy now stored in the elastically deformed, or compressed bumper. In addition, the detent 56 which had momentarily retracted when the enlarged head 57 of the carrier moved therepast to engage the bumper 48, has now returned to a projecting condition behind and below the enlarged head 57 of the carrier as shown in FIG. 2.

With the carrier and detent in the position shown in FIG. 2 and the bumper 48 elastically compressively deformed, the bumper applies a force in the direction of arrow 52 against the forward end 50 of the carrier. This bumper force, which is applied uniformly across the face of the forward end 50 of the carrier, can be considered as a single force B acting in the direction of arrow 52 along the carrier axis at a perpendicular distance D from the detent 56 about which the carrier pivots. The bumper force B applies a counterclockwise moment to the carrier having a magnitude proportioned to the product of B and D, which tends to pivot the carrier about the detent 56 in a counterclockwise direction.

Also tending to pivot the carrier counterclockwise about the detent 56 is the combined weight W of the carrier and the contents. Assuming the contents of the carrier are uniformly distributed spacially in the carrier, the combined weight W of the carrier and contents can be assumed to act vertically downwardly in the direction of arrow 80 through the center of gravity CG of the carrier which is located along the carrier axis midway between the opposite ends 14 and 50 thereof. The combined weight W of the carrier and contents applies a counterclockwise moment to the carrier about the detent 56 having a magnitude correlated to the product of W and X, where X is the perpendicular distance between the detent 56 and the direction of arrow 80 through which the weight W acts.

The combined effect of moments WX and BD, both acting in the same counterclockwise direction, is to pivot the carrier counterclockwise about the detent 56. As the carrier pivots from the position shown in FIG. 2 to the position shown in FIG. 3, and thence to the position shown in FIG. 4, the lower end 14 thereof moves outwardly through the exit opening 64 (FIG. 3). Eventually the enlarged head 57 of the carrier, which at the start of the pivotal carrier motion about detent 56 was engaged with the detent, becomes disengaged therefrom, allowing the lower end 14 of the carrier to slideably engage the guide panel 72. Following further pivoting and sliding engagement of the carrier and guide panel 72, the carrier eventually comes to rest with the end 14 thereof against the abutment 76, the body portion of the carrier between heads 57 and thereof supported by guide panel 72, and the enlarged head 57 engaged with the guide panel edge 74. In this position, the insertion end 22 of the transmit tube 20 is blocked and the received carrier conveniently disposed for manual removal by an operator (FIG. 4).

FIGS. 8, 9, 10 and 11 depict possible modifications 108, 208, 308 and 408 of the terminal 8 shown in FIGS. l7, in which the angulation of the respective terminal tube sections 142, 242, 342 and 442 thereof vary with respect to each other and with respect to the angulation of terminal tube section 42 of the terminal 8 shown in FIGS. 17. Except for the angulation of the terminal tube sections 142, 242, 342 and 442 terminals 108, 208, 308 and 408, respectively, of FIGS. 8, 9, 10 and 11, respectively, the terminals shown in these figures are in all other respects structurally identical to the terminal 8 depicted in FIGS. 1-7. Accordingly, elements in the terminals 108, 208, 308, and 408 of FIGS. 8-11 which are identical to corresponding elements of terminal 8 of FIGS. 1-7 bear reference numerals which are identical to those in FIGS. l-7.

In the preferred embodiment of the invention depicted in FIGS. 1-7, the axis A of the terminal tube section 42 at the upper end 46 thereof is inclined with respect to the horizontal at an angle of approximately 60 as indicated by angle 89. In contrast, in the modified embodiments of FIGS. 8, 9, 10 and 1 1, the axis A of the terminal tube sections 142, 242, 342 and 442 at the upper ends thereof is angled with respect to the horizontal at approximately 0, 30, and as indicated by angles 189, 289, 389, and 489, respectively. In each of the embodiments of FIGS. 8-11 a received carrier compresses the bumper 48, pivots counterclockwise about the detent 56, and eventually comes to rest supported on the guide panel 72 with its lower end 14 against the abutment 76. Necessary counterclockwise pivotal action of the carrier about the detent 56 in the embodiment of FIGS. 8-11 will occur providing that the counterclockwise moment BD exerted by the compressed bumper 48 against the carrier end 50 tending to pivot it counterclockwise about detent 56 exceeds any clockwise moment WX, should one exist, produced by the combined weight W of the carrier and its contents acting through the perpendicular distance between the detent 56 and a vertical line through which the weight W of the carrier and content acts which, as indicated, passes through the center of gravity CG of the carrier and contents. Should the contents of the carrier not be uniformly spatially distributed in the carrier and, for example, fall to the bottom of the carrier, the center of gravity of the carrier and contents, through which the combined weight W of the carrier and content acts, is closer to the lower end 14 of the carrier than the forward end 50.

With reference to FIG. 12 depicting the compressed bumper 48, detent 56 engaged therewith, and carrier C in approximately the disposition found in the embodiment of FIGS. 17, it is clear that the moment BD exerted on the carrier by the compressed bumper 48 and the moment WX exerted on the carrier as a consequence of its own weight and that of the uniformly distributed contents therein, both act to pivot the carrier in a counterclockwise direction about the detent 56. In accordance with this embodiment wherein the moment WX is counterclockwise, the carrier will pivot in the desired manner as previously described even if the force B exerted on the carrier by the compressed bumper should go to zero.

FIG. 13 depicts a carrier, bumper and detent in the orientation they would occupy in the embodiment of FIG. 10 wherein the terminal tube section 342 is oriented at approximately 90 with respect to the horizontal. In this embodiment the bumper force B and the combined weight W of the carrier and contents act in the same direction and along the same line, namely, vertically downwardly, through the center of gravity CG of the carrier, with the perpendicular distances D and X between the detent 56 and the lines' of forces B and W being identical, i.e. distance D equals distance X. Like the embodiment depicted in FIG. 12, the embodiment of FIG. 13 will also cause the received carrier to pivot counterclockwise about the detent 56, as desired, even though the bumper force may goto zero.

FIG. 14 depicts an embodiment in which the combined weight W of the carrier and its contents acting vertically downwardly through the center of gravity CG of the carrier, passes through the detent 56 with the result that distance X equals zero. With distance X equally zero the moment WX also equals zero with the result that the weight of the carrier does not assist pivoting of the carrier in the desired counterclockwise direction about the detent 56. Assuming the bumper force B is greater than zero, the moment BD will exceed zero, causing the carrier to pivot counterclockwise about detent 56, as desired.

FIG. 15 depicts a modification in which the combined weight W of the carrier and its contents acting vertically downwardlythrough the center of gravity CG of the carrier is displaced rightwardly of the detent 56, with the result that the moment WX applied to the carrier as a consequence of the combined weight W of carrier and contents operates to apply a clockwise moment to the carrier about detent 56. In accordance with this moidication, the carrier will only pivot in the desired counterclockwise direction about the detent 56 if the moment BD produced by the compressed bumper 48 which is in the counterclockwise direction exceeds the moment WXwhich is in the clockwise direction. In this modification, the-force B applied by the bumper to the forward end of the carrier 50 is essential to effect the desired counterclockwise pivoting of the received carrier about detent 56.

We claim:

1. A pneumatic system for receiving carriers, comprising:

a system receiving tube having an exit end through which received carriers moving in a forward direc tion exit,

a terminal tube section having a first end communicating with said exit end of said system receiving tube through which received carriers moving in a forward direction pass following exit from said system receiving tube, said terminal tube section having a second end and an elongated intermediate tube region located between said terminal tube section ends,

brake means, including an elastically-deformable braking element mounted at said second end of said terminal tube section, for arresting the forward motion of a received carrier moving in said intermediate tube region and thereafter forceably directing said carrier rearwardly in a reverse direction, said braking element becoming elastically deformed incidental to carrier arrest and thereafter becoming undeformed incidental to carrier reversal,

a pivot member mounted proximate said second end of said terminal tube section at a point to engage the forward end of a received carrier at the periphery thereof and cause it to pivot thereabout as it is reversely directed by said brake means, the rear end of said pivoting carrier moving through an are having a specified radius as said carrier pivots about said pivot member, and

a carrier opening in the side of said intermediate tube region through which a pivoting carrier reversely directed by said brake means is adapted to exit from said intermediate tube region, said opening extending from said pivot member in a direction toward said first end of said terminal tube section a distance approximating said radius of said arc through which the rear end of a received carrier moves when the forward end thereof pivots about said pivot member.

2. The system of claim 1 further including a carrier guide means extending outwardly and downwardly from said carrier opening for slidably engaging the rear end of a pivoting carrier as it passes through said carrier opening to guide the carrier to a position substantially outside said intermediate tube region with the rear end thereof remote from said carrier opening and the carrier overlying said guide means and supported thereby.

3. The system of claim 2 further including an abutment mounted remote from said carrier opening and engageable with said rear end of said carrier to arrest said sliding motion of said carrier while engaged by said underlying guide'means thereby supporting said carrier stationarily outside said terminal tube section.

4. The system of claim 1 wherein the said elastically deformable element is a compressible bumper secured to said second end of said terminal tube section to abut the forward end of a received carrier and become compressed in the process of arresting forward carrier motion.

5. The system of claim 3 further including a system transmit tube having a carrier insertion end located between said abutment and carrier opening, said transmit tube insertion end adapted to be blocked by a received carrier supported on said guide means to prevent insertion therein of a carrier to be transmitted, said insertion end being adapted to receive inserted carriers for transmission when unblocked by a carrier supported on said guide means.

6. The system of claim 4 wherein said pivot member is a deflectable detent normally extending into said intermediate tube region for engagement with a received carrier, having an enlarged head at the forward end thereof, at a point slightly rearwardly of said enlarged head when the forward end of said received carrier abuts said bumper.

7. The system of claim 1 wherein said system receive tube is disposed to discharge carriers from the exit end thereof with a substantial vertically upwardly directed component of forward motion, and wherein said intermediate tube region is disposed to have a substantial vertical component proximate said second end thereof, and wherein said carrier guide means is disposed to have a substantial horizontal component to facilitate convenient manual removal therefrom. 

1. A pneumatic system for receiving carriers, comprising: a system receiving tube having an exit end through which received carriers moving in a forward direction exit, a terminal tube section having a first end communicating with said exit end of said system receiving tube through which received carriers moving in a forward direction pass following exit from said system receiving tube, said terminal tube section having a second end and an elongated intermediate tube region located between said terminal tube section ends, brake means, including an elastically-deformable braking element mounted at said second end of said terminal tube section, for arresting the forward motion of a received carrier moving in said intermediate tube region and thereafter forceably directing said carrier rearwardly in a reverse direction, said braking element becoming elastically deformed incidental to carrier arrest and thereafter becoming undeformed incidental to carrier reversal, a pivot member mounted proximate said second end of said terminal tube section at a point to engage the forward end of a received carrier at the periphery thereof and cause it to pivot thereabout as it is reversely directed by said brake means, the rear end of said pivoting carrier moving through an arc having a specified radius as said carrier pivots about said pivot member, and a carrier opening in the side of said intermediate tube region through which a pivoting carrier reversely directed by said brake means is adapted to exit from said intermediate tube region, said opening extending from said pivot member in a direction toward said first end of said terminal tube section a distance approximating said radius of said arc through which the rear end of a received carrier moves when the forward end thereof pivots about said pivot member.
 2. The system of claim 1 further including a carrier guide means extending outwardly and downwardly from said carrier opening for slidably engaging the rear end of a pivoting carrier as it passes through said carrier opening to guide the carrier to a position substantially outside said intermediate tube region with the rear end thereof remote from said carrier opening and the carrier overlying said guide means and supported thereby.
 3. The system of claim 2 further including an abutment mounted remote from said carrier opening and engageable with said rear end of said carrier to arrest said sliding motion of said carrier while engaged by said underlying guide means thereby supporting said carrier stationarily outside said terminal tube section.
 4. The system of claim 1 wherein the said elastically deformable element is a compressible bumper secured to said second end of saiD terminal tube section to abut the forward end of a received carrier and become compressed in the process of arresting forward carrier motion.
 5. The system of claim 3 further including a system transmit tube having a carrier insertion end located between said abutment and carrier opening, said transmit tube insertion end adapted to be blocked by a received carrier supported on said guide means to prevent insertion therein of a carrier to be transmitted, said insertion end being adapted to receive inserted carriers for transmission when unblocked by a carrier supported on said guide means.
 6. The system of claim 4 wherein said pivot member is a deflectable detent normally extending into said intermediate tube region for engagement with a received carrier, having an enlarged head at the forward end thereof, at a point slightly rearwardly of said enlarged head when the forward end of said received carrier abuts said bumper.
 7. The system of claim 1 wherein said system receive tube is disposed to discharge carriers from the exit end thereof with a substantial vertically upwardly directed component of forward motion, and wherein said intermediate tube region is disposed to have a substantial vertical component proximate said second end thereof, and wherein said carrier guide means is disposed to have a substantial horizontal component to facilitate convenient manual removal therefrom. 